When I was in college, I had one of those literature professors who literally didn't know what she was talking about. She would tell us one day that the story of Oedipus Rex was the story of a man's relationship with Fate, over which the gods had no control (according to her own words), only to give us a quiz the next day where we were supposed to answer that the story dealt with man's relationship to god because Oedipus's fate was told through Apollo's oracle and therefore it was Apollo's will. When I called her on it after class, she decided she would change my grade since I apparently cared so much but the other losers who had answered based on her own lecture would just have to deal with it. Another time she tried to convince the class that Paul had founded the church in Rome when his own letter to the Roman church apologized for the fact that he had never been to Rome. Every class, it was something different where she was trying to change the story, change the history, or change her own words. By the end of the semester I was fighting the urge to mumble under my breath throughout the entire class period and skipped once or twice just to avoid damaging my testimony. No, I'm not joking. I just don't do well when people try to change the truth.
In Paul's letter to the Galatians, Paul was defending the Gospel he had preached to the churches in Galatia from the influence of people who wanted to convince Gentile believers that they had to become full-fledged Jews, surgery included, if they wanted to be saved. Paul did not respond well to their influence. Paul wrote, "I am a amazed that you are so quickly turning away from Him who called you by the grace of Christ and are turning to a different gospel, not that there is another gospel, but there are some who are troubling you and want to change the good news about the Messiah. But even if we or an angel from heaven should preach to you a gospel other than what we have preached to you, a curse be on him!" (Galatians 1:7-9, HCSB).
Paul wanted the Galatians to remember that any "gospel" which did not rest on the foundation that God saves us by grace through faith because of Jesus' crucifixion and resurrection was not, in fact, "good news." And he pointed out that certain people wanted to literally change the Gospel. We live in a world today where people all around us want to change the Gospel. They don't like the idea that the grace of God, given through Jesus is the only way to be saved (John 14:6) and so they change it. They don't like the idea that certain behaviors and lifestyles are sinful according to God's word, and so they undermine scripture while claiming to accept it and try to change the Word of God. Some groups want to make the Gospel more exclusive than it is and claim that a person has to speak in tongues in order to be saved, and they change the Gospel.
In the course of your life, and likely in the course of your week, you will encounter people who want to change the Gospel. When that time comes, will people be amazed that you are so quickly turning away from Him who called you by the grace of Christ or will you stand firm in the truth of the Gospel you have received? Will you abandon the truth you have accepted over the course of your life for the sake of a good sounding argument over the course of a few minutes?
False gospels are presented every day. Will you accept them or hold fast to the truth you believed when Jesus made Himself known to you?